(1) Field of the Invention
This invention generally relates to an apparatus for flexure testing long, slender shapes.
More particularly, the invention relates to an apparatus for flexure testing long, slender shapes such as solid or hollow structural beams, tubes, pipes, cylinders, and the like in which a length of the specimen under test is not limited and the orientation of the specimens is not limited by a position of load columns on a load application device.
(2) Description of the Prior Art
The current art for flexure testing limit the specimen length to an inside distance between load columns of a load application device and require specimens to be oriented within the plane defined by the load columns.
The following patents, for example, disclose flexure testing, but do not disclose flexure testing in which a specimen is aligned perpendicularly to the load column plane such that no restriction is imposed on specimen length.
Specifically, Glassmeyer (U.S. Pat. No. 3,898,873) discloses an intermodel cargo container bottom lift tested by means of a test fixture including adjustable supports which are connected to the lower corner fittings to maintain the container in a raised position free of a supporting surface. The upper corner fittings are first connected to a suitable hoisting device and upon lifting are placed in tension. The lower corner fitting lifting capability of the container is then tested by releasing the tension in the cables, the bottom lift test fixtures being placed in compression.
Hayashi (U.S. Pat. No. 4,590,900) discloses a valve supporting arrangement of an internal combustion engine. The upper retainer is for retaining an upper portion of a valve spring shaped like a perforated spinning top and is axially dividable into two identical elements which are coaxially disposed about the upper portion of the valve stem when assuming its operative condition. The retainer has, when assuming the operative position, a configuration which comprises a collar portion which is sized to be coaxially disposed within an upper portion of the valve spring, an annular flange portion extending radially outward from the upper end of the collar portion and engaging with the upper end of the valve spring, and means for achieving a spline connection between the central portion of the retainer and the upper portion of the valve stem.
Maciejczak (U.S. Pat. No. 4,789,947) discloses, in conjunction with an unmanned, remotely controllable apparatus for inspecting, testing and viewing and for examination and evaluation of the general condition, state of repair, and of the quality of fabrication of mechanical structures including bridges, an assembly including a guide track carried by a space frame fastened to extend transversely of a bridge or other structure at an underside thereof. The track supports a carrier adapted for transporting, viewing, examining, treating and testing apparatus for controlled movement and manipulation of the apparatus along a path delineated by the guide track. In a preferred embodiment of the invention the carrier supports one or more turntables and one or more articulated arms and linked arm assemblies at remote ends of which selectable viewing and testing devices are attachable. The space frame itself may be moved lineally along the bridge, on an underside thereof so that through the combination of the transversely moving carrier and the lineally movable space frame, an entire aerial zone may be traversed.
Strong (U.S. Pat. No. 5,345,826) discloses a static load tester that provides tensile testing of plated test specimens to detect hydrogen embrittlement damage from plating processes. The functional components of the device are centrally aligned within a channel of an I-beam frame. A load cell and electronic readout provide the user with a measure of the tensile force applied to up to eight test specimens mounted end to end in a tester. Tension is applied to the specimens through use of a simple threaded rod and nut load application system at the base of the device. A static load tester may be incorporated into each channel of the I-beam frame, thereby providing a double testing unit. Additionally, a series of I-beam frame tester configurations may be incorporated into one multiple testing unit. Each multiple testing unit has a number of static load testers equal to double the number of I-beam frames mounted into the unit. The tension applied to any individual tester in a multiple testing unit may be displayed on a single electronic readout through use of a switch box coupled between the individual testers and the readout.
Diaz et al. (U.S. Pat. No. 5,386,442) discloses an apparatus and a method for measuring and controlling the crack growth rate within a double cantilever beam type test specimen. The arms of the test specimen are fitted with a pressure-actuated bellows to induce a predetermined load and with a sensing assembly to provide feedback on the amount of beam displacement resulting from the application of that load. In this manner, a loaded test specimen may be remotely mounted and adjusted inside the reactor pressure vessel or piping of a nuclear reactor in order to maintain a stress intensity which is constant or which varies in a predetermined manner for inducing stress corrosion cracking or corrosion fatigue in the specimen.
Tucchio (U.S. Pat. No. 5,448,918) discloses a biaxial compression testing device formed by two modified beams joined together to form an X-shape with the support structure, such as webs and upper flanges, removed in the region of the X intersection, thereby leaving a rectangular opening. The rectangular opening has dimensions slightly greater than the widths of the beams and is open from the upper surfaces downward to the lower surfaces which are joined together forming an X-configuration. This configuration has a flexing characteristic in the direction perpendicular to the plane of the joined beams. A test specimen support plate is attached to the underside of one of the upper surfaces and is located so as to slide below the opposing upper surface during flexing of the X-beam assembly. Each beam is supported by a roller pin. Additional roller pins are located on the specimen support plate between each beam upper flange and a specimen to be tested. The single actuating force is applied to cause the X-beams to flex into a concave shape thereby applying a part of the actuating force axially along each beam. The configuration provides a force transfer assembly which is actuated by a single load force, but provides a biaxial load to the test specimen.
Starostovic, Jr. (U.S. Pat. No. 5,699,274) discloses a performance testing system, i.e., performance of a material under a load concentrated in a single area. The system is computerized and automatically applies a load to a panel to be tested, reads and records deflection of the panel without operator involvement, and provides a printed test report.
Simonelli et al. (U.S. Pat. No. 5,913,246) discloses a machine for the cyclic load testing in tension, compression, torsion, shear, or any combination thereof of any one of a number of different sizes, types and configurations of test specimens at a fixed or adjustable predetermined load and cycle rate and comprising a machine frame in which is mounted a drive shaft, any number of intermediate shafts as required, and a camshaft or crankshaft. At the workstation of the machine, appropriate fixtures and tooling are either fixed, rotating, or in motion, as required to conduct the particular test to be performed. When the test specimen is to be in motion, the motion may be derived from a driving source separate from the primary mover or camshaft, for instance, but not limited to an independent motor or cylinder. This source of motion may also be taken through a drive train or any suitable means from the same driving source as the camshaft or from the camshaft itself or from any other moving member in the system. A motion is ultimately imparted to drive the test specimen bolder, thereby setting the test specimen in motion.
Miller et al. (U.S. Pat. No. 6,042,315) discloses a fastener body comprising a head and a shank fabricated from a composite material. The head has at least one side which extends beyond the side of the shank and has two other sides coplanar with the shank. A fastener for engaging a liner has perpendicular lengthwise and widthwise reference axes and a head and a shank, with the shank extending in a first lengthwise direction away from the head, the head further having at least one extension that extends in the widthwise direction beyond the shank for engaging the liner, wherein substantially all lengthwise directed load components transmitted from the liner to the head are transmitted through the extension.
Starostovic (U.S. Pat. No. 5,699,274) discloses a performance testing system for woodbased panels. The testing includes performance of a material under a load concentrated in a single area, performance of edge support systems under a concentrated load and performance of a material under static bending conditions. The system is computerized and automatically applies a load to a panel to be tested, reads and records deflection of the panel without operator involvement, and provides a printed test report.
Zhou (U.S. Pat. No. 6,216,531) discloses an adapter for use in the testing of shear strength of an adhesive as applied to a test specimen. The adapter has a structure that permits it to be used on testing machines either in a tension or in a compression mode. The adapter as a testing tool includes a pair of coacting force blocks which slidably engage each other and move relative to each other. Each such force block has a central opening into which a test specimen may be inserted. The openings in each of the force blocks engage a different one of the two test coupons that make up a testing specimen. The force blocks further have bearing surfaces that oppose each other so that they may engage the like opposing ends of the test specimen.
It should be understood that the present invention would in fact enhance the functionality of the above patents by providing an adjustable apparatus for supporting long span beams in a flexure testing machine regardless of their length or orientation.